Bioware has released some new information as well as a trailer for their upcoming Resurgence Pack:

“The Mass Effect 3 Resurgence Pack adds new unlockable content: deadly weapons, new consumables, and powerful characters for each class in multiplayer, including the Asari Justicar, Batarian, Geth, and Krogan Battlemaster. Additionally, the Mass Effect 3 Resurgence Pack also includes 2 new maps, Firebase Condor and Firebase Hydra. Download this pack on April 10th and take the battle online in the critically acclaimed Mass Effect 3 multiplayer experience.”